THE attainment gap between the richest and poorest school students has widened, according to a new breakdown of Highers grades.

Research by the Scottish Conservatives, based on a series of Freedom of Information requests, found pupils from the most affluent backgrounds were seven times more likely to gain three As at Higher than those from the least well off families.

Across Scotland, just under three per cent of pupils from the most deprived 20 per cent of households obtained the grades, seen as a benchmark for university entrance.

By contrast, just over 21 per cent of students from the most affluent 20 per cent of families achieved three As in S5 last year.

In four education authority areas, Argyll & Bute, Dumfries & Galloway, East Lothian and Midlothian, no pupils at all from the poorest backgrounds got the grades.

In the best-performing area, South Ayrshire, only seven per cent achieved three As at Higher.

At the other end of the scale, more than a third of the richest students in East Renfrewshire reached the same standard.

Comparing the figures with the previous year, the Scots Tories said the overall attainment gap had widened by almost one per cent.

Scots Tory leader Ruth Davidson challenged Nicola Sturgeon on the figures during First Minister's Questions, when she claimed the Scottish Government was doing too little to tackle the problem.

Speaking later she said: "We already knew the SNP was failing to close the attainment gap, now we know it’s actually getting wider.

"The Scottish Government has completely failed to make it easier for the most disadvantaged children to have the same opportunities as their wealthier counterparts.

"Nicola Sturgeon keeps saying she wants the SNP to be judged on its record.

"In education, that record is one of failure, and the experts say her plans won’t fix it."

She added: "The Scottish Government needs to offer a proper explanation as to why it’s failing these children after more than eight years in government."

Ms Sturgeon said raising overall attainment while closing the gap between rich and poor students was her number one priority when she took office last year.

Since then, however, figures have shown a decline in standards in primary schools.

A report earlier this week from the Reform Scotland think tank questioned whether  Scottish Government initiatives, including a £100million fund to support schools in the most deprived areas, would be effective in closing the attainment gap.

Ms Sturgeon told MSPs there had been some progress towards closing the attainment gap with 40 per cent of pupils from the 20 per cent most deprived areas getting at least one higher, up from 23 per cent in 2007.

She said: "I am not standing here, I never have stood here and said that there's not more work to do.

"But we are seeing in many respects evidence of the attainment gap narrowing."

She said 300 primary schools were already benefitting from the new fund, which is a key part of its "national improvement framework".

Ms Sturgeon also defended plan to re-introduce a system of national testing for primary schools.

Willie Rennie, the Scottish Lib Dem leader, criticised the move, which will allow league tables to be compiled.

But Ms Sturgeon told him: "I stand by what I said.

"I have no interest in crude league tables that offer no meaning to parents, nor do I have any interest in a system that would encourage teaching to the test.

"But I do think it is incumbent on me as First Minister to make sure that children's progress is being assessed in a way that better informs the judgements teachers make about their performance, and also that allow all of us to have a meaningful and evidenced debate about whether we are or are not making progress in closing the attainment gap."